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1.
Mol Cell Biol ; 41(10): e0008121, 2021 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-34251884

RESUMO

Cullin-4 ubiquitin ligase (CRL4) complexes are differentially composed and highly dynamic protein assemblies that control many biological processes, including the global genome nucleotide excision repair (GG-NER) pathway. Here, we identified the kinase mitogen-activated protein kinase kinase kinase 1 (MEKK1) as a novel constitutive interactor of a cytosolic CRL4 complex that disassembles after DNA damage due to the caspase-mediated cleavage of MEKK1. The kinase activity of MEKK1 was important to trigger autoubiquitination of the CRL4 complex by K48- and K63-linked ubiquitin chains. MEKK1 knockdown prohibited DNA damage-induced degradation of the CRL4 component DNA-damage binding protein 2 (DDB2) and the CRL4 substrate p21 and also cell recovery and survival. A ubiquitin replacement strategy revealed a contribution of K63-branched ubiquitin chains for DNA damage-induced DDB2/p21 decay, cell cycle regulation, and cell survival. These data might also have implications for cancer, as frequently occurring mutations of MEKK1 might have an impact on genome stability and the therapeutic efficacy of CRL4-dependent immunomodulatory drugs such as thalidomide derivatives.


Assuntos
Reparo do DNA/fisiologia , MAP Quinase Quinase Quinase 1/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Sobrevivência Celular , Inibidor de Quinase Dependente de Ciclina p21/genética , DNA/química , Dano ao DNA/fisiologia , Reparo do DNA/genética , Proteínas de Ligação a DNA/metabolismo , Células HEK293 , Células HeLa , Humanos , MAP Quinase Quinase Quinase 1/genética , Proteínas Nucleares/metabolismo , Ubiquitina-Proteína Ligases/fisiologia , Ubiquitinação
2.
J Cardiovasc Dev Dis ; 5(3)2018 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-30217061

RESUMO

Purpose: Fasting or postprandial hypertriglyceridemia is considered an independent cardiovascular disease (CVD) risk factor. The intestinal fatty acid binding protein (FABP2) is involved in the intracellular transport and metabolism of fatty acids. The presence of the Ala54Thr polymorphism of the FABP2 gene appears to be involved in postprandial hypertriglyceridemia. We explored the possible association of the Ala54Thr polymorphism with fat intolerance in apparently healthy, fasting, normolipidemic subjects with normal body-mass index and without diabetes. Methodology: A total of 158 apparently healthy individuals were classified as fat tolerant (n = 123) or intolerant (n = 35) according to their response (plasma triglycerides) to an oral abbreviated tolerance test with blood samples taken at 0, 2 and 4 h. At 0 h, all subjects ingested 26.3 g of fats. Presence of the Ala54Thr polymorphism of the FABP2 gene was evaluated by polymerase chain reaction⁻restriction fragment length (PCR⁻RFLP). Results: The group with fat intolerance (postprandial hypertriglyceridemia group) showed an increased frequency of the Thr54Thr genotype when compared with the group with normal fat tolerance (control group) (23% vs. 4%, respectively, OR: 16.53, 95% CI: 4.09⁻66.82, p: 0.0001, pc: 0.0003). Carriers of at least one Thr54 allele were up to six times more prevalent in the fat intolerant group than in the non-carriers. (OR: 6.35; 95% CI: 1.86⁻21.59, p: 0.0003, pc: 0.0009). The levels of plasma triglycerides (Tg) at 4 h after the test meal were higher in carriers of at least one 54Thr allele than in carriers of the Ala54 allele (p < 0.05). Conclusions: There is a significant association between postprandial hypertriglyceridemia and the presence of at least one 54Thr allele of the FABP2 gene. In addition, subjects with this genotype showed an increased ratio of Tg/HDL-cholesterol. This parameter is a marker of increased CVD risk and insulin resistance.

3.
Methods Mol Biol ; 1510: 297-312, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27761830

RESUMO

The family of seven-in-absentia (SIAH) ubiquitin E3 ligases functions in the control of numerous key signaling pathways. These enzymes belong to the RING (really interesting new gene) group of E3 ligases and mediate the attachment of ubiquitin chains to substrates, which then leads to their proteasomal degradation. Here, we describe a protocol that allows measuring SIAH-mediated ubiquitination and degradation of its client proteins as exemplified by acetyl transferases using simple overexpression experiments. The impact of SIAH expression on the relative amounts of target proteins and their mRNAs can be quantified by Western blotting and quantitative PCR (qPCR) as described here.


Assuntos
Proteínas Nucleares/metabolismo , Processamento de Proteína Pós-Traducional , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina/metabolismo , Fatores de Transcrição de p300-CBP/metabolismo , Eletroforese em Gel de Poliacrilamida/métodos , Expressão Gênica , Células HEK293 , Humanos , Proteínas Nucleares/antagonistas & inibidores , Proteínas Nucleares/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Transfecção , Ubiquitina/genética , Ubiquitina-Proteína Ligases/antagonistas & inibidores , Ubiquitina-Proteína Ligases/genética , Ubiquitinação , Fatores de Transcrição de p300-CBP/genética
4.
Arch. venez. pueric. pediatr ; 79(2): 54-61, jun. 2016. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-827837

RESUMO

La obesidad resulta de los efectos combinados de los genes, el ambiente y el estilo de vida. La leptina (LEP) y el receptor de leptina (LEPR) son genes que han sido evaluados en la búsqueda de variantes que podrían estar relacionadas con la obesidad y sus complicaciones cardiometabólicas. Objetivo: Evaluar la posible asociación entre los polimorfismos G2548A del gen LEP y Gln223Arg del gen LEPR con el desarrollo de obesidad y resistencia a la insulina (RI) en niños y adolescentes pre-púberes. Métodos: Se estudiaron 314 niños de 2-11 años, clasificados según los parámetros antropométricos y bioquímicos en: a) sobrepeso/obesos sin RI (n=133), b) sobrepeso/obesos con RI (n=75) y c) controles sanos (n=70). La genotipificación fue realizada por reacción en cadena de la polimerasapolimorfismos de longitud de fragmentos de restricción (PCR-RFLP); se estudiaron las asociaciones entre genotipo y riesgo, y se compararon los promedios de las medidas antropométricas y bioquímicas. Resultados: La frecuencia genotípica para el polimorfismo G2548A del gen LEP fue 51% G/A, 33% G/G y 16% A/A; para el polimorfismo Gln223Arg del gen LEPR fue Gln/Arg 49%, Gln/Gln 31% y Arg/Arg 20%. Se encontró diferencia significativa en la distribución de los diferentes genotipos del gen de LEPR en los niños con sobrepeso/obesidad y RI con respecto al grupo control (OR= 2,6; IC 95%=1,17-5,75; p < 0.05). Conclusión: Se observó una asociación entre la presencia del genotipo Gln/Gln del gen LEPR con la RI (factor de riesgo cardiometabólico), presentando los niños con sobrepeso/obesidad y RI 2,6 veces más riesgo a presentar RI.


Obesity is a result of the combined effects of genes, environment and lifestyle. The Leptin (LEP) and leptin receptor (LEPR) are genes that have been extensively evaluated in search for variants that may be associated with obesity and cardiometabolic complications. Objective: To evaluate the possible association between polymorphisms G2548A of the LEP gene and Gln223Arg of the LEPR gene with the development of obesity and insulin resistance (IR) in prepubertal children and adolescents. Methods: We studied 314 children 2-11 years, grouped by anthropometric and biochemical parameters: a) overweight /obese without IR (n = 133), b) overweight /obese with IR (n = 75) and c) healthy controls (n = 70). Genotyping was performed by Polymerase Chain Reaction-Restriction Fragment Length Polymorphisms (PCR-RFLP) method. Genotype-risk associations were studied. We then compared the average values for anthropometric and biochemical parameters. Results: The genotypic frequency for polymorphism G2548A of LEP gene was 51% for the G/A genotype, 33% G/G and 16% A/A genotype; for polymorphism Gln223Arg of LEPR gene was of Gln/Arg 49%, Gln/Gln 31% and Arg/Arg 20%. Significant difference was found in the distribution of different genotypes of the LEPR gene in children with overweight/obesity with IR compared to the control group (OR = 2.6; 95% CI = 1.17 to 5.75; p < 0.05). Conclusion: We observed an association between the presence of Gln/Gln genotype of the LEPR gene with insulin resistance (cardiometabolic risk factor) children, rendering these children with overweight/obese with IR 2,6 times more likely to be with insulin.

5.
Mol Biol Cell ; 27(12): 1969-80, 2016 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-27122605

RESUMO

The serine/threonine kinase HIPK2 functions as a regulator of developmental processes and as a signal integrator of a wide variety of stress signals, such as DNA damage, hypoxia, and reactive oxygen intermediates. Because the kinase is generated in a constitutively active form, its expression levels are restricted by a variety of different mechanisms. Here we identify the CCR4-NOT complex as a new regulator of HIPK2 abundance. Down-regulation or knockout of the CCR4-NOT complex member CNOT2 leads to reduced HIPK2 protein levels without affecting the expression level of HIPK1 or HIPK3. A fraction of all HIPK family members associates with the CCR4-NOT components CNOT2 and CNOT3. HIPKs also phosphorylate the CCR4-NOT complex, a feature that is shared with their yeast progenitor kinase, YAK1. Functional assays reveal that HIPK2 and HIPK1 restrict CNOT2-dependent mRNA decay. HIPKs are well known regulators of transcription, but the mutual regulation between CCR4-NOT and HIPKs extends the regulatory potential of these kinases by enabling posttranscriptional gene regulation.


Assuntos
Proteínas de Transporte/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Repressoras/metabolismo , Fatores de Transcrição/metabolismo , Proteínas de Transporte/genética , Dano ao DNA , Humanos , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Fosforilação , Proteínas Serina-Treonina Quinases/genética , Receptores CCR4/metabolismo , Transdução de Sinais , Técnicas do Sistema de Duplo-Híbrido
6.
J Appl Lab Med ; 1(3): 250-259, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33626837

RESUMO

BACKGROUND: Postprandial increase of triglyceride-rich lipoproteins augments the risk of atherosclerotic cardiovascular disease and all-cause mortality. We explored the hypothesis that a simplified oral fat tolerance test can uncover differences in postprandial triglyceride response associated with potentially atherogenic lipoprotein characteristics, even in a cohort of apparently healthy 31-year-old [mean (SD), 31 (11)] nonobese individuals with normal fasting lipids and lipoproteins. METHODS: We used a fat tolerance test in 96 females and 62 males with blood sampled at 0, 2, and 4 h after a breakfast containing 26.3 g of fats. The postprandial triglyceride response was used to classify the individuals in apparently fat-tolerant and apparently fat-intolerant participants. RESULTS: The intolerant individuals were found to have at 0 h significantly higher body mass index, plasma triglycerides, remnant cholesterol, VLDL cholesterol, and LDL cholesterol and lower apolipoprotein (apo) AI and HDL cholesterol than the tolerant individuals. More than 70% of the variability (r2) of the postprandial response in tolerant and intolerant individuals measured as area under the curve or, at a single point at 4 h after the oral fat load, was linearly correlated with 0-h triglycerides (P < 0001). Fasting lipoprotein parameters, proposed to be markers of cardiovascular risk, as the ratios apo B/apo AI, total cholesterol/HDL cholesterol, and triglycerides/HDL cholesterol, were increased in the intolerant individuals. CONCLUSIONS: A simplified oral fat tolerance test, even when used in an apparently healthy, nonobese, normolipidemic cohort, detected that an increased postprandial triglycerides response was associated with augmented lipoprotein markers of increased cardiovascular risk.

7.
Arch. venez. pueric. pediatr ; 78(1): 18-26, mar. 2015. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-772673

RESUMO

Introducción: El sustrato del receptor de insulina 1 (IRS1) es un componente importante de la cascada de transducción de señales de la insulina y podría estar relacionado con los trastornos metabólicos asociados al síndrome metabólico. Objetivo: Evaluar el papel del polimorfismo Gly972Arg del gen IRS1 con factores de riesgo cardiometabólicos en niños pre-púberes. Metodología: Se estudiaron 279 niños con edades comprendidas entre 2-12 años, clasificados según los parámetros antropométricos y bioquímicos en: a) niños obesos sin RI (n=135), b) niños obesos con RI (n=80) y c) niños controles sanos (n=64). A cada niño se le realizó una extracción de sangre en ayunas y una postprandial, para determinar glicemia e insulina basal y postprandial, triglicéridos, colesterol total y fraccionado y la frecuencia genotípica del SNP Gly972Arg. Resultados: Se observó que 37,5% de los niños presentó RI; 9,6% hiperglicemia en ayunas; 27,3% hipertrigliceridemia y 50,46% bajos niveles de HDL-c. La frecuencia genotípica fue 89% genotipo Gly/Gly y 11% genotipo Gly/Arg. Se encontró diferencia significativa en la distribución de los diferentes genotipos del gen de IRS1 en los niños con sobrepeso/obesidad sin RI y niños con sobrepeso/obesidad con RI con respecto al grupo control (OR= 4,47; IC 95%=0,96-16,92; p < 0,05) y (OR= 4,43; IC 95%=0,93-21,00; p < 0,05) respectivamente. Conclusión: Se observó una asociación entre la presencia del genotipo Gly/Arg del gen IRS1 con sobrepeso/obesidad (factor de riesgo cardiometabólico) en los niños del estudio, presentando estos niños 4 veces más riesgos a presentar sobrepeso/obesidad que los niños con el genotipo Gly/Gly.


Introduction: Insulin receptor substrate 1 (IRS-1) is an important component of the insulin signal transduction cascade and could be related with metabolic disorders associated with metabolic syndrome (MS). Aim: Evaluate the role of the Gly972Arg polymorphism in the IRS1 gene in prepubertal children with cardiometabolic risk factors. Methods: We studied 279 children between 2-12 years of age, divided in groups 3 groups: a) obese children without insulin resistance (IR) (n=135), b) obese children with IR (n=80) and c) healthy children as controls (n=64). Basal and postprandial glucose, insulin, triglycerides, total and fractionated cholesterol and genotype frequency of the Gly972Arg SNP were determined in fasting and postprandial samples in each child. Results: 37.5% of the children had IR; in the fasting state, 9.6% had hyperglycemia, 27.3% hypertriglyceridemia and 50.46 % low HDL-C. The genotypic frequency was 89% for the Gly / Gly genotype and 11% Gly / Arg genotype. Significant difference was found in the distribution of the different genotypes of the IRS1 gene in children with overweight/obesity without IR and children with overweight/obesity with IR compared to the control group (OR = 4.47;CI 95% = 0.96-16.92; p <0.05) and (OR = 4.43; CI 95%= 0.93 - 21.00, p <0.05) respectively. Conclusion: Association between the presence of Gly/Arg genotype of the IRS1 gene with overweight/obesity (cardiometabolic risk factor) was observed in the studied children. These children were four times more likely to be overweight/obese than children with Gly / Gly genotype.

8.
Acta cient. Soc. Venez. Bioanalistas Esp ; 16(1): 28-40, 2013. tab, graf
Artigo em Espanhol | LILACS | ID: lil-733453

RESUMO

Las enfermedades cardiovasculares y el síndrome metabólico son patologías que afectan a gran parte de la población mundial, de etiología poligénica y multifactorial, resultado de la interacción entre factores genéticos, ambientales, sociales y culturales. Los principales genes candidatos a estudiar son aquellos relacionados con la regulación de la homeostasis de la glucosa, del metabolismo lipídico y/o de la secreción y acción de la insulina, como son el gen de los Receptores de los Proliferadores Perixosomales Activados gamma 2 (PPARγ2), la Proteína Enlazante de Ácidos Grasos Intestinal (FABP2) y la Apolipoproteína E (ApoE). Evaluar la relación entre los polimorfismos Pro12Ala del gen PPARγ2, Ala54Thr del gen FABP2 y del gen de ApoE en habitantes del Sector “Los Eucaliptos” de la Parroquia San Juan. 308 individuos de dicha comunidad, 98 hombres y 210 mujeres, clasificados en hipercolesterolémicos, hipertrigliceridémicos, resistentes a la insulina y controles de acuerdo a sus niveles de colesterol total, triglicéridos e índice HOMA. Extracción de 10 mL de sangre venosa para la determinación de química sanguínea y extracción de ADN, amplificación mediante PCR de un fragmento de 102pb del gen de PPARγ2, uno de 180pb del gen de FABP2 y otro de 244pb del gen de ApoE, y posterior RFLP. Se encontró una frecuencia alélica de 0,91 para el alelo Pro y 0,09 para el Ala del gen de PPARγ2; 0,70 para el alelo Ala del gen FABP2 y 0,30 para el Thr, mientras que para los alelos del gen de ApoE la frecuencia fue de ε2=0,05, ε3=0,80 y ε4=0,15. Se encontró relación entre el alelo ε4 de ApoE y la hipercolesterolemia, además del alelo ε2 como factor protector ante el desarrollo de hipercolesterolemia, hipertrigliceridemia y resistencia a la insulina, no encontrándose asociación alguna entre los polimorfismos de los restantes genes y las patologías mencionadas.


Cardiovascular disease and metabolic syndrome are diseases that affect worldwide, with multiple genetic and environmental components contributing to susceptibility. The main candidate genes to study are those related to the regulation of glucose homeostasis, lipid metabolism, insulin secretion and action and obesity, these include the genes for Peroxisome proliferator-activated receptor gamma 2 (PPARγ2), fatty acid-binding protein 2 (FABP2) and Apolipoprotein E (Apo E). The aim of this study was to investigate the relationship between polymorphisms of Pro12Ala PPARγ2 gene, Ala54Thr FABP2 gene and the ApoE gene in residents from the “The Eucaliptus” of the “Parroquia San Juan”. 308 subjects, 98 men and 210 women, classified as hypercholesterolemic, hypertriglyceridemic, insulin resistant and controls according to their levels of total cholesterol, triglycerides and HOMA index. Extraction of 10 mL whole blood for determination of chemistry and DNA extraction, PCR amplification of a 102 bp fragment PPARγ2 gene, a 180 bp FABP2 gene and a 244 bp of ApoE gene, and subsequent RFLP. An allele frequency for allele Pro 0.91 and 0.09 for gene PPARγ2 Ala and 0.70 for the allele of the gene FABP2 Ala and 0.30 for Thr, while for the different alleles of ApoE gene frequency was ε2=0.05, ε3=0.80 and ε4=0.15. We found a relationship between the ApoE ε4 allele and hypercholesterolemia, in the other hand, Apo E ε2 allele was found as a protective factor against the development of hypercholesterolemia, hypertriglyceridemia and insulin resistance, we did not found association between polymorphisms of the other genes and the pathologies mentioned above.


Assuntos
Humanos , Masculino , Adulto , Feminino , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/etiologia , Insulina/análise , Insulina/genética , Insulina/química , Polimorfismo Genético , Síndrome Metabólica/complicações , Síndrome Metabólica/diagnóstico , Análise Química do Sangue , Transtornos do Metabolismo de Glucose , Hematologia , Transtornos do Metabolismo dos Lipídeos
9.
Arch. venez. pueric. pediatr ; 75(3): 75-83, sep. 2012. tab
Artigo em Espanhol | LILACS | ID: lil-676430

RESUMO

La resistencia a la insulina es muy frecuente en niños y adolescentes obesos, la cual conlleva a un significativo riesgo de desarrollar enfermedades cardiometabólicas causadas por la combinación de factores genéticos y factores asociados al estilo de vida. Evaluar la relación entre los polimorfismos del gen ApoE y el polimorfismo Pro12Ala del gen PPARγ2 en niños pre-púberes con factores de riesgo cardiometabólicos. Población y Métodos: Se evaluaron 141 niños (CANIA y Hospital “JM de los Ríos”), de los cuales 46 tienen obesidad, 33 hipercolesterolemia, 30 resistentes a la insulina (RI) y 32 controles. Se determinó colesterol total y fracciones, triglicéridos, glucosa, insulina e índice HOMA; se realizó extracción de ADN y análisis de los polimorfismos. La distribución de la frecuencia del alelo ε4 del gen de ApoE fue: 10,9% obesos, 7,6% hipercolesterolémicos, 18,3% RI y 4,6% controles. La frecuencia del polimorfismo Pro12Ala fue de 6,4% en la población estudiada. En los niños obesos e hipercolesterolémicos se observó aumento de colesterol total, LDL-c y triglicéridos asociados con la presencia del ε4; en el grupo con RI, se encontró que existen diferencias estadísticamente significativas entre el alelo ε4 con respecto al grupo control, lo que refiere que puede haber una relación clínica importante entre la presencia del alelo y el desarrollo de la enfermedad. No se encontró relación entre el polimorfismo Pro12Ala del gen PPARγ2 con factores de riesgo cardiometabólico. La presencia de varios polimorfismos en un mismo individuo podría estar asociada a factores de riesgo para enfermedad cardiometabólica


Insulin resistance (IR) is very frequent in children and adolescents obeses, which could contribute significantly in the development of cardiometabolic diseases, this could be associated to a combination of genetics factors and life’s style. Aim: To evaluate the relationship between ApoE gene polymorphisms and PPARγ2 gene Pro12Ala polymorphisms with risk factors to cardiometabolic disease in children. Population and Materials: 141 children (CANIA and Hospital “JM de los Ríos”), 46 with obesity, 33 with hypercholesterolemia, 30 with IR and 32 normal subjects. Total cholesterol and fractions, glucose, insulin and triglycerides were measured; also it was determinated the polymorphism genes on each patient. Results: The distribution of the frequency of the allele E4 of the ApoE gene were: 10, 9% obese, 7,6% hypercholesterolemia, 18,3% IR and 4,6% on normal subjects. The frequency of Pro12Ala polymorphism were up to 6,4% on the total subjects in the study. In the obese and hypercholesterolemic groups we found an increase of the total cholesterol, LDL-c and triglycerides, associated with the presence of allele ε4. In children with IR we got a significant difference of the presence of allele ε4 compared with the control group, which means that this allele could be related with the development of thedisease. It was not found a relation between the Pro12Ala of PPARγ2 gene and the development of obesity, hypercholesterolemia and insulin resistance in children. The presence of several polymorphisms in a same individual could be associated with risk factors to cardiometabolic disease


Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Criança , Apolipoproteínas E/genética , Doenças Metabólicas/patologia , Hipercolesterolemia/patologia , Resistência à Insulina , Traumatismos Cardíacos/patologia , Obesidade/patologia , Polimorfismo Genético , Pediatria , Fatores de Risco
10.
Acta cient. Soc. Venez. Bioanalistas Esp ; 13-15(1): 49-54, 2010-2012. tab
Artigo em Espanhol | LILACS | ID: lil-733429

RESUMO

La Hiperhomociteinemia (HHcy) se considera como un factor de riesgo idenpendiente para el desarrollo de aterosclerosis y de enfermedad arterial coronaria (EAC). Los polimorfismos en encimas involucradas en la regulación del metabolismo de la Hcy como la metiltetrahidrofolato reductasa (MTHFR), metionina sintasa (MTR), y la metionina sintasa reductasa (MTRR) pueden contribuir a la variación de los niveles de homocisteína en plasma (Hcy). En este estudio investigamos la asociación de los polimorfismos genéticos de las enzimas involucradas en la remetilación de la homocisteínia: metionina sintasa (MTR), metil N-tetrahidrofolato reductasa (MTHFR) y metionina sintasa reductasa (MTRR), con los niveles de Hcy en pacientes con EAC y sujetos sanos. Población 136 individuos de los cuales 90 presentaron diagnóstico de enfermedad cardiovascular (IAM y ACV) y 46 eran aparentemente sanos (controles). La concentración de Hcy fue significativamente más alta en pacientes con ECV que en los sujetos control (P<0,001). HHcy (>15 µmol/L) confirió un RR de IAM de 2.52 (95% IC: 1.4-4.4, P<0,001) y de ACV de 1.88 (95% IC: 1.0-3-5, P<0,05). Los niveles de vitamina B12 y folato se encontraba en el rango de los valores de referencia en el 86% de los individuos. La frecuencia del alelo T para C677T de MTHFR, del alelo G para A66G de MTRR y del alelo G para A2756G de MTR fueron 0.31, 0.30, 0.22 respectivamente para los sujetos casos. Los polimorfismos C677T, A66G y A276G de los genes MTHFR, MTRR y MTR no tuvieron diferencia estadísticamente significativa entre el grupo de casos con respecto al grupo control. Los polimorfismos estudiados no se relacionaron estadísticamente con la HHcy en los individuos en estudio. Sugerimos que HHcy confiere riesgo para ECV. En nuestro estudio encontramos evidencia de que la regulación de Hcy es poligénica.


The Hiperhomocysteinemia (HHcy) is considered an independent risk factor for developing atherosclerosis and cardiovascular arterial disease (CAD). The polymorphisms of the enzymes involved in the regulation of homocysteine (Hcy) metabolism as the methyltetrahydrofolate reductase (MTHFR), methionine synthase (MTR) and methionine synthase reductase (MTRR) may contribute to the elevation of Hcy in plasma. The main aim of the this study was to investigate the association of genetic polymorphisms of the enzymes involved in remethylation of homocysteine: methionine synthase (MTR), N-methyl tetrahydrofolate reductase (MTHFR) and methionine synthase reductase (MTRR), with levels of Hcy in patients with CHF and healthy subjects. Population: 136 subjects of whom 90 had a diagnosis of cardiovascular disease (heart failure and stroke) and 46 were apparently healthy (controls). The concentration of Hcy was significantly higher in patients with cardiovascular disease than compare with the control group (P<0.001). HHcy (>15 mmol/L) conferred a relative risk (RR) of heart failure of 2.52 (95% CI: 1.4-4.4, P <0.001) and stroke, RR of 1.88 (95% CI: 1.0-3.5, P <0.05). The levels of vitamin B12 and folate was in the range of reference values in 86% of subjects. The frequency of the T allele of MTHFR C677T was 0,31, for the G allele of MTRR A66G was 0,30 and for the G allelwe for MTR A2756G was 0.22 for the subjects with heart failure and stroke referred as case. C677T polymorphism, A66G and A2756G of the genes MTHFR, MTRR and MTR had no associated statistically with HHcy in the subjects of the study. We suggest that HHcy confers risk for CVD. In our study we found evidence that the regulation of Hcy is polygenic.


Assuntos
Humanos , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/sangue , Enzimas/análise , Enzimas/sangue , Homocisteína/análise , Homocisteína/sangue , Polimorfismo Genético/genética , Análise Química do Sangue , Hematologia
11.
Arch. venez. pueric. pediatr ; 73(4): 8-14, dic. 2010. ilus, graf
Artigo em Espanhol | LILACS | ID: lil-659151

RESUMO

La ateroesclerosis comienza en etapas tempranas de la vida y la disfunción endotelial se reconoce como el acontecimiento inicial dominante en su desarrollo. Estudiar marcadores de inflamación y disfunción endotelial en niños con infección bacteriana. Se estudiaron 36 niños (6 meses-10 años 11 meses) hospitalizados con diagnóstico de infección bacteriana. Se tomó sangre venosa en tres fases: I (fase aguda infección, ingreso), II (convalecencia, 1 semana post-admisión), III (recuperación, 1 mes postadmisión). 32 niños sanos de la consulta. En todos los pacientes y controles se determinó: colesterol total y fracciones, triglicéridos, proteínas totales y fraccionadas, PCR ultrasensible (PCRus), sICAM-1, sVCAM-1, IL-6, óxido nítrico. En los niños con infección se encontró: 1) niveles de colesterol total elevados: aumento en las fracciones de LDL-C y LP(a)- C en la fase I con el pico en fase II y disminución con la recuperación del niño, 2) aumento del perfil inflamatorio mediado por IL-6, con el subsecuente aumento de la PCRus y alfa 2 globulinas, las cuales disminuyen en la fase de recuperación. Los marcadores de disfunción endotelial sVCAM-1 e sICAM-1 aumentan en la fase I y disminuyen con la recuperación. Los marcadores de inflamación (IL-6, PCRus) mantienen correlación positiva con los marcadores de disfunción endotelial (sVCAM-1 e sICAM-1). Los niveles de óxido nítrico estuvieron disminuidos en las tres fases. La infección aguda bacteriana en la niñez se asocia al aumento de los marcadores inflamatorios, lo cual apoya el papel potencial de éstos en la patogénesis de la ateroesclerosis temprana


Markers of inflammation and endothelial dysfunction in children with bacterial infections. Atherosclerosis begins early in life and endothelial dysfunction is recognized as the key initiating event in the development of atherosclerosis. To study biomarkers of inflammation and endothelial dysfunction in children with bacterial infection. The study included 36 children (6 months-10 years 11 months) hospitalized with the diagnosis of bacterial infection. Venous blood was extracted in three phases: I (acute phase of infection, entry), II (convalescence, 1 week post-admission), III (recovery, 1 month post-admission). 32 children who attended the healthy children outpatient clinic were the control group. The following parameters were assessed in all patients and controls: cholesterol and its fractions, triglycerides, total and fractionated proteins, high sensitivity C-reactive protein (hsCRP), sICAM-1, sVCAM-1, IL-6, nitric oxide. Children with infection had high total cholesterol levels with increased LDL-C and Lp (a)-C fractions in phase I, rising to a peak in phase II and decreasing as the child recovers. Infected children also had an increased inflammatory profile mediated by IL-6, with the subsequent increase in hsCRP and alpha 2 globulin, which decrease as the child recovers. Endothelial dysfunction markers sVCAM-1 and sICAM-1 increase at admission and decrease as the child recovers. Inflammation markers (IL-6, hsCRP) correlate positively with markers of endothelial dysfunction (sVCAM-1 and sICAM-1). Nitric oxide levels are decreased in all three phases. Acute infection in childhood is associated with damage to the endothelium. These results support the potential role of inflammatory stimuli in the pathogenesis of early atherosclerosis


Assuntos
Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Células Endoteliais , Mediadores da Inflamação , Infecções Bacterianas/diagnóstico , Inflamação/patologia , Biomarcadores/análise , Pediatria
12.
Cell Immunol ; 264(1): 86-92, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20553754

RESUMO

Human NK cells are classified into two populations according to the intensity of CD56 surface expression, as well as possession of CD16, FcRIII. CD56(dim)CD16(bright) make up 90% circulating NK cells, whereas CD56(bright)CD16(-/dim) comprises the remaining 10%. Here we report that peripheral NK cells upon CD16 cross-linking up-regulates the expression of activating markers and receptors such as CD25, CD69, NKp44, NKp30, CD40L and the intensity of CD56 expression. Additionally, co-culturing immature DCs with CD16 activated NK cells was found to significantly increase the expression of maturation markers on DCs. These results suggest that CD16 cross-linking on resting peripheral blood NK cells triggers the activation of these cells and induces the appearance of CD56(bright) NK cells. The latter were found capable of producing pro-inflammatory cytokines, IFN-gamma and TNF-alpha and notably IL-12.


Assuntos
Antígeno CD56/biossíntese , Células Dendríticas/metabolismo , Células Matadoras Naturais/metabolismo , Subpopulações de Linfócitos/metabolismo , Receptores de IgG/metabolismo , Antígeno CD56/genética , Diferenciação Celular , Células Cultivadas , Técnicas de Cocultura , Células Dendríticas/imunologia , Células Dendríticas/patologia , Humanos , Imunofenotipagem , Interleucina-12/metabolismo , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/patologia , Ativação Linfocitária , Subpopulações de Linfócitos/imunologia , Subpopulações de Linfócitos/patologia , Receptor 2 Desencadeador da Citotoxicidade Natural/biossíntese , Receptor 3 Desencadeador da Citotoxicidade Natural/biossíntese , Agregação de Receptores , Receptores de IgG/imunologia
13.
Acta cient. Soc. Venez. Bioanalistas Esp ; 12(1): 111-121, 2009. tab, graf
Artigo em Espanhol | LILACS | ID: lil-733450

RESUMO

El estado pospandrial constituye la condición metabólica habitual en la que se encuentra el ser humani diariamente. Algunos sujetos presentan aumento de los triglicéridos totales y de las lipoproteíneas ricas en trigléceridos totales y de las lipoproteínas ricas en triglicéridos definiéndose como hiperlipemica pospandrial, generando incrementos del estrés oxidativo, inflamación y disfunción vascular, además está asociada con el riesgo de enfermedad cardiovascular, que en los últimos años se ha convertido en la principal causa de muerte en todo el mundo. El objetivo del esudio fue evaluar la relación entre los niveles de triglicéridos pospandriales de sujetos cardiópatas y accidente cerebrovascular (ACV) con sujetos aparentemente sanos. Se estudiaron 56 sujetos de los cuales 32 eran aparentemente sanos (clasificados según sus resultados de triglicéridos pospandriales en intolerantes a las grasas y tolerancia normal a las grasas), 11 con diagnóstico de cardiopatía y 13 con diagnóstico de ACV. A cada paciente se les realizó un extracción de sangre basal con 14 horas de ayuno, posteriormente se les suministró un desayuno de aproximadamente 24 gr de grasa (una empanada de queso y un café). Se tomó muestras para el estudio de los niveles de triglicéridos (basal y pospandrial 2 y 4 horas), colesterol total y sus fracciones, apolipoproteina A1 y B-100, fibrinógeno y proteína C reactiva ultrasensible. Se realizó TBARS para estimar los niveles de oxidación de las LDL y la prueba de afinidd de las LDL a proteoglicanos. Mediante ecodoppler se evaluó el complejo miointimal carotideo. Los pacientes cardiópatas e intolerantes a las grasas tuvieron niveles de triglicéridos por encima de los valores de referencia a las 2 y 4 horas después de comer (p<0,001). Las LDL del grupo de cardiópatas y ACV presentaron mayor afinidad a proteoglicanos y mayor oxidación que las LDL del grupo intolerante y normal (p<0,001)...


The postpandrial nonfasting state is the usual metabolic condition in the human. Some individuals had increased total triglycerides and triglyceride-rich lipoproteins, defined as postprandial hyperlipidemia, generatin an increase in oxidative stress, inflammation and vascular dysfunction also is associated with cardiovascular disease risk, which in recent years has become the leading cause of death worldwide. Aim: Evaluate the realtionship between postpandrial triglyceride levels of subjects with heart disease and stroke with apparently halthy subjects. We studied 56 subjects of whom 32 were apparently healthy (classified according to their results of postprandial triglyceride in fat intolerant and normal tolerance to fat), 11 have diagnosis of heart disease and 13 with diagnosis of stroke. From every patient, we withdrew blood after 14 hours of fasting as baseline, then were given a breakfast of about 24gr of fat (a typical venezuelan breakfast, which consisted in a cheese emapana and coffe). Samples were taken at basal time and 2 and 4 hours postpandrial o measure levels of triglicerides and also measure total cholesterol and its fractions, apolipoprotein A1 and B-100, fibrinogen and C-reactive protein. TBARS was performed to estimate the levels of LDL oxidation and proof affinity of LDL to proteoglycans. To evaluate the myointimal carotid complex we used a duplex Doppler echo. Patients with hearth disease and intolerance to fat had triglyceride levels above baseline values at 2 and 4 hours after eating (p<0.001). The level of LDL in the group of heart disease and stroke had higher affinity for proteoglycans and increased LDL oxidation than intolerant and normal group (p<0.001). The ratio Chol / HDL and LDL / HDL was higher in the intolerant and heart disease, indicating a risk factor for cardiovascular disease. The postprandial triclyceride measurement seems to be a better predictor of cardiovascular risk than measurement levels of triclyceride in...


Assuntos
Humanos , Masculino , Adulto , Feminino , Acidente Vascular Cerebral/etiologia , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/etiologia , Glicemia/análise , Glicemia/química , Doenças Metabólicas , Triglicerídeos/química , Triglicerídeos/sangue , Análise Química do Sangue , Hematologia , Hiperlipidemias/complicações
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